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Dependencies: mbed ros_lib_kinetic
PID.cpp@1:40bdbe1a93b7, 2018-06-22 (annotated)
- Committer:
- Knillinux
- Date:
- Fri Jun 22 02:09:50 2018 +0000
- Revision:
- 1:40bdbe1a93b7
- Parent:
- 0:dd126a1080d3
Updates
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| Knillinux | 0:dd126a1080d3 | 1 | /** |
| Knillinux | 0:dd126a1080d3 | 2 | * @author Aaron Berk |
| Knillinux | 0:dd126a1080d3 | 3 | * |
| Knillinux | 0:dd126a1080d3 | 4 | * @section LICENSE |
| Knillinux | 0:dd126a1080d3 | 5 | * |
| Knillinux | 0:dd126a1080d3 | 6 | * Copyright (c) 2010 ARM Limited |
| Knillinux | 0:dd126a1080d3 | 7 | * |
| Knillinux | 0:dd126a1080d3 | 8 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| Knillinux | 0:dd126a1080d3 | 9 | * of this software and associated documentation files (the "Software"), to deal |
| Knillinux | 0:dd126a1080d3 | 10 | * in the Software without restriction, including without limitation the rights |
| Knillinux | 0:dd126a1080d3 | 11 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| Knillinux | 0:dd126a1080d3 | 12 | * copies of the Software, and to permit persons to whom the Software is |
| Knillinux | 0:dd126a1080d3 | 13 | * furnished to do so, subject to the following conditions: |
| Knillinux | 0:dd126a1080d3 | 14 | * |
| Knillinux | 0:dd126a1080d3 | 15 | * The above copyright notice and this permission notice shall be included in |
| Knillinux | 0:dd126a1080d3 | 16 | * all copies or substantial portions of the Software. |
| Knillinux | 0:dd126a1080d3 | 17 | * |
| Knillinux | 0:dd126a1080d3 | 18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| Knillinux | 0:dd126a1080d3 | 19 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| Knillinux | 0:dd126a1080d3 | 20 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| Knillinux | 0:dd126a1080d3 | 21 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| Knillinux | 0:dd126a1080d3 | 22 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| Knillinux | 0:dd126a1080d3 | 23 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| Knillinux | 0:dd126a1080d3 | 24 | * THE SOFTWARE. |
| Knillinux | 0:dd126a1080d3 | 25 | * |
| Knillinux | 0:dd126a1080d3 | 26 | * @section DESCRIPTION |
| Knillinux | 0:dd126a1080d3 | 27 | * |
| Knillinux | 0:dd126a1080d3 | 28 | * A PID controller is a widely used feedback controller commonly found in |
| Knillinux | 0:dd126a1080d3 | 29 | * industry. |
| Knillinux | 0:dd126a1080d3 | 30 | * |
| Knillinux | 0:dd126a1080d3 | 31 | * This library is a port of Brett Beauregard's Arduino PID library: |
| Knillinux | 0:dd126a1080d3 | 32 | * |
| Knillinux | 0:dd126a1080d3 | 33 | * http://www.arduino.cc/playground/Code/PIDLibrary |
| Knillinux | 0:dd126a1080d3 | 34 | * |
| Knillinux | 0:dd126a1080d3 | 35 | * The wikipedia article on PID controllers is a good place to start on |
| Knillinux | 0:dd126a1080d3 | 36 | * understanding how they work: |
| Knillinux | 0:dd126a1080d3 | 37 | * |
| Knillinux | 0:dd126a1080d3 | 38 | * http://en.wikipedia.org/wiki/PID_controller |
| Knillinux | 0:dd126a1080d3 | 39 | * |
| Knillinux | 0:dd126a1080d3 | 40 | * For a clear and elegant explanation of how to implement and tune a |
| Knillinux | 0:dd126a1080d3 | 41 | * controller, the controlguru website by Douglas J. Cooper (who also happened |
| Knillinux | 0:dd126a1080d3 | 42 | * to be Brett's controls professor) is an excellent reference: |
| Knillinux | 0:dd126a1080d3 | 43 | * |
| Knillinux | 0:dd126a1080d3 | 44 | * http://www.controlguru.com/ |
| Knillinux | 0:dd126a1080d3 | 45 | */ |
| Knillinux | 0:dd126a1080d3 | 46 | |
| Knillinux | 0:dd126a1080d3 | 47 | /** |
| Knillinux | 0:dd126a1080d3 | 48 | * Includes |
| Knillinux | 0:dd126a1080d3 | 49 | */ |
| Knillinux | 0:dd126a1080d3 | 50 | #include "PID.h" |
| Knillinux | 0:dd126a1080d3 | 51 | |
| Knillinux | 0:dd126a1080d3 | 52 | PID::PID(float Kc, float tauI, float tauD, float interval) { |
| Knillinux | 0:dd126a1080d3 | 53 | |
| Knillinux | 0:dd126a1080d3 | 54 | usingFeedForward = false; |
| Knillinux | 0:dd126a1080d3 | 55 | inAuto = false; |
| Knillinux | 0:dd126a1080d3 | 56 | |
| Knillinux | 0:dd126a1080d3 | 57 | //Default the limits to the full range of I/O: 3.3V |
| Knillinux | 0:dd126a1080d3 | 58 | //Make sure to set these to more appropriate limits for |
| Knillinux | 0:dd126a1080d3 | 59 | //your application. |
| Knillinux | 0:dd126a1080d3 | 60 | setInputLimits(0.0, 3.3); |
| Knillinux | 0:dd126a1080d3 | 61 | setOutputLimits(0.0, 3.3); |
| Knillinux | 0:dd126a1080d3 | 62 | |
| Knillinux | 0:dd126a1080d3 | 63 | tSample_ = interval; |
| Knillinux | 0:dd126a1080d3 | 64 | |
| Knillinux | 0:dd126a1080d3 | 65 | setTunings(Kc, tauI, tauD); |
| Knillinux | 0:dd126a1080d3 | 66 | |
| Knillinux | 0:dd126a1080d3 | 67 | setPoint_ = 0.0; |
| Knillinux | 0:dd126a1080d3 | 68 | processVariable_ = 0.0; |
| Knillinux | 0:dd126a1080d3 | 69 | prevProcessVariable_ = 0.0; |
| Knillinux | 0:dd126a1080d3 | 70 | controllerOutput_ = 0.0; |
| Knillinux | 0:dd126a1080d3 | 71 | prevControllerOutput_ = 0.0; |
| Knillinux | 0:dd126a1080d3 | 72 | |
| Knillinux | 0:dd126a1080d3 | 73 | accError_ = 0.0; |
| Knillinux | 0:dd126a1080d3 | 74 | bias_ = 0.0; |
| Knillinux | 0:dd126a1080d3 | 75 | |
| Knillinux | 0:dd126a1080d3 | 76 | realOutput_ = 0.0; |
| Knillinux | 0:dd126a1080d3 | 77 | |
| Knillinux | 0:dd126a1080d3 | 78 | } |
| Knillinux | 0:dd126a1080d3 | 79 | |
| Knillinux | 0:dd126a1080d3 | 80 | void PID::setInputLimits(float inMin, float inMax) { |
| Knillinux | 0:dd126a1080d3 | 81 | |
| Knillinux | 0:dd126a1080d3 | 82 | //Make sure we haven't been given impossible values. |
| Knillinux | 0:dd126a1080d3 | 83 | if (inMin >= inMax) { |
| Knillinux | 0:dd126a1080d3 | 84 | return; |
| Knillinux | 0:dd126a1080d3 | 85 | } |
| Knillinux | 0:dd126a1080d3 | 86 | |
| Knillinux | 0:dd126a1080d3 | 87 | //Rescale the working variables to reflect the changes. |
| Knillinux | 0:dd126a1080d3 | 88 | prevProcessVariable_ *= (inMax - inMin) / inSpan_; |
| Knillinux | 0:dd126a1080d3 | 89 | accError_ *= (inMax - inMin) / inSpan_; |
| Knillinux | 0:dd126a1080d3 | 90 | |
| Knillinux | 0:dd126a1080d3 | 91 | //Make sure the working variables are within the new limits. |
| Knillinux | 0:dd126a1080d3 | 92 | if (prevProcessVariable_ > 1) { |
| Knillinux | 0:dd126a1080d3 | 93 | prevProcessVariable_ = 1; |
| Knillinux | 0:dd126a1080d3 | 94 | } else if (prevProcessVariable_ < 0) { |
| Knillinux | 0:dd126a1080d3 | 95 | prevProcessVariable_ = 0; |
| Knillinux | 0:dd126a1080d3 | 96 | } |
| Knillinux | 0:dd126a1080d3 | 97 | |
| Knillinux | 0:dd126a1080d3 | 98 | inMin_ = inMin; |
| Knillinux | 0:dd126a1080d3 | 99 | inMax_ = inMax; |
| Knillinux | 0:dd126a1080d3 | 100 | inSpan_ = inMax - inMin; |
| Knillinux | 0:dd126a1080d3 | 101 | |
| Knillinux | 0:dd126a1080d3 | 102 | setSetPoint(setPoint_); |
| Knillinux | 0:dd126a1080d3 | 103 | } |
| Knillinux | 0:dd126a1080d3 | 104 | |
| Knillinux | 0:dd126a1080d3 | 105 | void PID::setOutputLimits(float outMin, float outMax) { |
| Knillinux | 0:dd126a1080d3 | 106 | |
| Knillinux | 0:dd126a1080d3 | 107 | //Make sure we haven't been given impossible values. |
| Knillinux | 0:dd126a1080d3 | 108 | if (outMin >= outMax) { |
| Knillinux | 0:dd126a1080d3 | 109 | return; |
| Knillinux | 0:dd126a1080d3 | 110 | } |
| Knillinux | 0:dd126a1080d3 | 111 | |
| Knillinux | 0:dd126a1080d3 | 112 | //Rescale the working variables to reflect the changes. |
| Knillinux | 0:dd126a1080d3 | 113 | prevControllerOutput_ *= (outMax - outMin) / outSpan_; |
| Knillinux | 0:dd126a1080d3 | 114 | |
| Knillinux | 0:dd126a1080d3 | 115 | //Make sure the working variables are within the new limits. |
| Knillinux | 0:dd126a1080d3 | 116 | if (prevControllerOutput_ > 1) { |
| Knillinux | 0:dd126a1080d3 | 117 | prevControllerOutput_ = 1; |
| Knillinux | 0:dd126a1080d3 | 118 | } else if (prevControllerOutput_ < 0) { |
| Knillinux | 0:dd126a1080d3 | 119 | prevControllerOutput_ = 0; |
| Knillinux | 0:dd126a1080d3 | 120 | } |
| Knillinux | 0:dd126a1080d3 | 121 | |
| Knillinux | 0:dd126a1080d3 | 122 | outMin_ = outMin; |
| Knillinux | 0:dd126a1080d3 | 123 | outMax_ = outMax; |
| Knillinux | 0:dd126a1080d3 | 124 | outSpan_ = outMax - outMin; |
| Knillinux | 0:dd126a1080d3 | 125 | } |
| Knillinux | 0:dd126a1080d3 | 126 | |
| Knillinux | 0:dd126a1080d3 | 127 | /*void PID::setConInputLimits(float cinMin, float cinMax) { |
| Knillinux | 0:dd126a1080d3 | 128 | |
| Knillinux | 0:dd126a1080d3 | 129 | //Make sure we haven't been given impossible values. |
| Knillinux | 0:dd126a1080d3 | 130 | if ((cinMin >= cinMax) || (cinMin < inMin_) || (cinMax > inMax_)) { |
| Knillinux | 0:dd126a1080d3 | 131 | return; |
| Knillinux | 0:dd126a1080d3 | 132 | } |
| Knillinux | 0:dd126a1080d3 | 133 | |
| Knillinux | 0:dd126a1080d3 | 134 | cinSMin_ = (cinMin - inMin_)/inSpan_; |
| Knillinux | 0:dd126a1080d3 | 135 | cinSMax_ = (cinMax - inMax_)/inSpan_; |
| Knillinux | 0:dd126a1080d3 | 136 | }*/ |
| Knillinux | 0:dd126a1080d3 | 137 | |
| Knillinux | 0:dd126a1080d3 | 138 | void PID::setTunings(float Kc, float tauI, float tauD) { |
| Knillinux | 0:dd126a1080d3 | 139 | |
| Knillinux | 0:dd126a1080d3 | 140 | //Verify that the tunings make sense. |
| Knillinux | 0:dd126a1080d3 | 141 | if (Kc == 0.0 || tauI < 0.0 || tauD < 0.0) { |
| Knillinux | 0:dd126a1080d3 | 142 | return; |
| Knillinux | 0:dd126a1080d3 | 143 | } |
| Knillinux | 0:dd126a1080d3 | 144 | |
| Knillinux | 0:dd126a1080d3 | 145 | //Store raw values to hand back to user on request. |
| Knillinux | 0:dd126a1080d3 | 146 | pParam_ = Kc; |
| Knillinux | 0:dd126a1080d3 | 147 | iParam_ = tauI; |
| Knillinux | 0:dd126a1080d3 | 148 | dParam_ = tauD; |
| Knillinux | 0:dd126a1080d3 | 149 | |
| Knillinux | 0:dd126a1080d3 | 150 | float tempTauR; |
| Knillinux | 0:dd126a1080d3 | 151 | |
| Knillinux | 0:dd126a1080d3 | 152 | if (tauI == 0.0) { |
| Knillinux | 0:dd126a1080d3 | 153 | tempTauR = 0.0; |
| Knillinux | 0:dd126a1080d3 | 154 | } else { |
| Knillinux | 0:dd126a1080d3 | 155 | tempTauR = (1.0 / tauI) * tSample_; |
| Knillinux | 0:dd126a1080d3 | 156 | } |
| Knillinux | 0:dd126a1080d3 | 157 | |
| Knillinux | 0:dd126a1080d3 | 158 | //For "bumpless transfer" we need to rescale the accumulated error. |
| Knillinux | 0:dd126a1080d3 | 159 | if (inAuto) { |
| Knillinux | 0:dd126a1080d3 | 160 | if (tempTauR == 0.0) { |
| Knillinux | 0:dd126a1080d3 | 161 | accError_ = 0.0; |
| Knillinux | 0:dd126a1080d3 | 162 | } else { |
| Knillinux | 0:dd126a1080d3 | 163 | accError_ *= (Kc_ * tauR_) / (Kc * tempTauR); |
| Knillinux | 0:dd126a1080d3 | 164 | } |
| Knillinux | 0:dd126a1080d3 | 165 | } |
| Knillinux | 0:dd126a1080d3 | 166 | |
| Knillinux | 0:dd126a1080d3 | 167 | Kc_ = Kc; |
| Knillinux | 0:dd126a1080d3 | 168 | tauR_ = tempTauR; |
| Knillinux | 0:dd126a1080d3 | 169 | tauD_ = tauD / tSample_; |
| Knillinux | 0:dd126a1080d3 | 170 | |
| Knillinux | 0:dd126a1080d3 | 171 | } |
| Knillinux | 0:dd126a1080d3 | 172 | |
| Knillinux | 0:dd126a1080d3 | 173 | void PID::reset(void) { |
| Knillinux | 0:dd126a1080d3 | 174 | |
| Knillinux | 0:dd126a1080d3 | 175 | float scaledBias = 0.0; |
| Knillinux | 0:dd126a1080d3 | 176 | |
| Knillinux | 0:dd126a1080d3 | 177 | if (usingFeedForward) { |
| Knillinux | 0:dd126a1080d3 | 178 | scaledBias = (bias_ - outMin_) / outSpan_; |
| Knillinux | 0:dd126a1080d3 | 179 | } else { |
| Knillinux | 0:dd126a1080d3 | 180 | scaledBias = (realOutput_ - outMin_) / outSpan_; |
| Knillinux | 0:dd126a1080d3 | 181 | } |
| Knillinux | 0:dd126a1080d3 | 182 | |
| Knillinux | 0:dd126a1080d3 | 183 | prevControllerOutput_ = scaledBias; |
| Knillinux | 0:dd126a1080d3 | 184 | prevProcessVariable_ = (processVariable_ - inMin_) / inSpan_; |
| Knillinux | 0:dd126a1080d3 | 185 | |
| Knillinux | 0:dd126a1080d3 | 186 | //Clear any error in the integral. |
| Knillinux | 0:dd126a1080d3 | 187 | accError_ = 0; |
| Knillinux | 0:dd126a1080d3 | 188 | |
| Knillinux | 0:dd126a1080d3 | 189 | } |
| Knillinux | 0:dd126a1080d3 | 190 | |
| Knillinux | 0:dd126a1080d3 | 191 | void PID::setMode(int mode) { |
| Knillinux | 0:dd126a1080d3 | 192 | |
| Knillinux | 0:dd126a1080d3 | 193 | //We were in manual, and we just got set to auto. |
| Knillinux | 0:dd126a1080d3 | 194 | //Reset the controller internals. |
| Knillinux | 0:dd126a1080d3 | 195 | if (mode != 0 && !inAuto) { |
| Knillinux | 0:dd126a1080d3 | 196 | reset(); |
| Knillinux | 0:dd126a1080d3 | 197 | } |
| Knillinux | 0:dd126a1080d3 | 198 | |
| Knillinux | 0:dd126a1080d3 | 199 | inAuto = (mode != 0); |
| Knillinux | 0:dd126a1080d3 | 200 | |
| Knillinux | 0:dd126a1080d3 | 201 | } |
| Knillinux | 0:dd126a1080d3 | 202 | |
| Knillinux | 0:dd126a1080d3 | 203 | void PID::setInterval(float interval) { |
| Knillinux | 0:dd126a1080d3 | 204 | |
| Knillinux | 0:dd126a1080d3 | 205 | if (interval > 0) { |
| Knillinux | 0:dd126a1080d3 | 206 | //Convert the time-based tunings to reflect this change. |
| Knillinux | 0:dd126a1080d3 | 207 | tauR_ *= (interval / tSample_); |
| Knillinux | 0:dd126a1080d3 | 208 | accError_ *= (tSample_ / interval); |
| Knillinux | 0:dd126a1080d3 | 209 | tauD_ *= (interval / tSample_); |
| Knillinux | 0:dd126a1080d3 | 210 | tSample_ = interval; |
| Knillinux | 0:dd126a1080d3 | 211 | } |
| Knillinux | 0:dd126a1080d3 | 212 | |
| Knillinux | 0:dd126a1080d3 | 213 | } |
| Knillinux | 0:dd126a1080d3 | 214 | |
| Knillinux | 0:dd126a1080d3 | 215 | void PID::setSetPoint(float sp) { |
| Knillinux | 0:dd126a1080d3 | 216 | |
| Knillinux | 0:dd126a1080d3 | 217 | if (sp > inMax_) { |
| Knillinux | 0:dd126a1080d3 | 218 | sp = inMax_; |
| Knillinux | 0:dd126a1080d3 | 219 | } else if (sp < inMin_) { |
| Knillinux | 0:dd126a1080d3 | 220 | sp = inMin_; |
| Knillinux | 0:dd126a1080d3 | 221 | } |
| Knillinux | 0:dd126a1080d3 | 222 | setPoint_ = sp; |
| Knillinux | 0:dd126a1080d3 | 223 | |
| Knillinux | 0:dd126a1080d3 | 224 | } |
| Knillinux | 0:dd126a1080d3 | 225 | |
| Knillinux | 0:dd126a1080d3 | 226 | void PID::setProcessValue(float pv) { |
| Knillinux | 0:dd126a1080d3 | 227 | |
| Knillinux | 0:dd126a1080d3 | 228 | processVariable_ = pv; |
| Knillinux | 0:dd126a1080d3 | 229 | |
| Knillinux | 0:dd126a1080d3 | 230 | } |
| Knillinux | 0:dd126a1080d3 | 231 | |
| Knillinux | 0:dd126a1080d3 | 232 | void PID::setBias(float bias){ |
| Knillinux | 0:dd126a1080d3 | 233 | |
| Knillinux | 0:dd126a1080d3 | 234 | bias_ = bias; |
| Knillinux | 0:dd126a1080d3 | 235 | usingFeedForward = 1; |
| Knillinux | 0:dd126a1080d3 | 236 | |
| Knillinux | 0:dd126a1080d3 | 237 | } |
| Knillinux | 0:dd126a1080d3 | 238 | |
| Knillinux | 0:dd126a1080d3 | 239 | void PID::setAccLimit(float accLimit) { |
| Knillinux | 0:dd126a1080d3 | 240 | |
| Knillinux | 0:dd126a1080d3 | 241 | accLimit_ = abs(accLimit); |
| Knillinux | 0:dd126a1080d3 | 242 | |
| Knillinux | 0:dd126a1080d3 | 243 | } |
| Knillinux | 0:dd126a1080d3 | 244 | |
| Knillinux | 0:dd126a1080d3 | 245 | |
| Knillinux | 0:dd126a1080d3 | 246 | float PID::compute() { |
| Knillinux | 0:dd126a1080d3 | 247 | |
| Knillinux | 0:dd126a1080d3 | 248 | //Pull in the input and setpoint, and scale them into percent span. |
| Knillinux | 0:dd126a1080d3 | 249 | float scaledPV = (processVariable_ - inMin_) / inSpan_; |
| Knillinux | 0:dd126a1080d3 | 250 | |
| Knillinux | 0:dd126a1080d3 | 251 | /*if (scaledPV > 1.0) { |
| Knillinux | 0:dd126a1080d3 | 252 | scaledPV = 1.0; |
| Knillinux | 0:dd126a1080d3 | 253 | } else if (scaledPV < 0.0) { |
| Knillinux | 0:dd126a1080d3 | 254 | scaledPV = 0.0; |
| Knillinux | 0:dd126a1080d3 | 255 | }*/ |
| Knillinux | 0:dd126a1080d3 | 256 | |
| Knillinux | 0:dd126a1080d3 | 257 | float scaledSP = (setPoint_ - inMin_) / inSpan_; |
| Knillinux | 0:dd126a1080d3 | 258 | /*if (scaledSP > 1.0) { |
| Knillinux | 0:dd126a1080d3 | 259 | scaledSP = 1.0; |
| Knillinux | 0:dd126a1080d3 | 260 | } else if (scaledSP < 0.0) { |
| Knillinux | 0:dd126a1080d3 | 261 | scaledSP = 0.0; |
| Knillinux | 0:dd126a1080d3 | 262 | }*/ |
| Knillinux | 0:dd126a1080d3 | 263 | |
| Knillinux | 0:dd126a1080d3 | 264 | error_ = scaledSP - scaledPV; |
| Knillinux | 0:dd126a1080d3 | 265 | |
| Knillinux | 0:dd126a1080d3 | 266 | //Check and see if the output is pegged at a limit and only |
| Knillinux | 0:dd126a1080d3 | 267 | //integrate if it is not. This is to prevent reset-windup. |
| Knillinux | 0:dd126a1080d3 | 268 | if (!(prevControllerOutput_ >= 1 && error_ > 0) && !(prevControllerOutput_ <= 0 && error_ < 0)) { |
| Knillinux | 0:dd126a1080d3 | 269 | accError_ += error_; |
| Knillinux | 0:dd126a1080d3 | 270 | if (accError_ > accLimit_) { |
| Knillinux | 0:dd126a1080d3 | 271 | accError_ = accLimit_; |
| Knillinux | 0:dd126a1080d3 | 272 | } else if (accError_ < -accLimit_) { |
| Knillinux | 0:dd126a1080d3 | 273 | accError_ = -accLimit_; |
| Knillinux | 0:dd126a1080d3 | 274 | } |
| Knillinux | 0:dd126a1080d3 | 275 | } |
| Knillinux | 0:dd126a1080d3 | 276 | |
| Knillinux | 0:dd126a1080d3 | 277 | //Compute the current slope of the input signal. |
| Knillinux | 0:dd126a1080d3 | 278 | float dMeas = (scaledPV - prevProcessVariable_) / tSample_; |
| Knillinux | 0:dd126a1080d3 | 279 | |
| Knillinux | 0:dd126a1080d3 | 280 | float scaledBias = 0.0; |
| Knillinux | 0:dd126a1080d3 | 281 | |
| Knillinux | 0:dd126a1080d3 | 282 | if (usingFeedForward) { |
| Knillinux | 0:dd126a1080d3 | 283 | scaledBias = (bias_ - outMin_) / outSpan_; |
| Knillinux | 0:dd126a1080d3 | 284 | } |
| Knillinux | 0:dd126a1080d3 | 285 | |
| Knillinux | 0:dd126a1080d3 | 286 | //Perform the PID calculation. |
| Knillinux | 0:dd126a1080d3 | 287 | controllerOutput_ = scaledBias + Kc_ * (error_ + (tauR_ * accError_) - (tauD_ * dMeas)); |
| Knillinux | 0:dd126a1080d3 | 288 | |
| Knillinux | 0:dd126a1080d3 | 289 | //Make sure the computed output is within output constraints. |
| Knillinux | 0:dd126a1080d3 | 290 | if (controllerOutput_ < 0.0) { |
| Knillinux | 0:dd126a1080d3 | 291 | controllerOutput_ = 0.0; |
| Knillinux | 0:dd126a1080d3 | 292 | } else if (controllerOutput_ > 1.0) { |
| Knillinux | 0:dd126a1080d3 | 293 | controllerOutput_ = 1.0; |
| Knillinux | 0:dd126a1080d3 | 294 | } |
| Knillinux | 0:dd126a1080d3 | 295 | |
| Knillinux | 0:dd126a1080d3 | 296 | //Remember this output for the windup check next time. |
| Knillinux | 0:dd126a1080d3 | 297 | prevControllerOutput_ = controllerOutput_; |
| Knillinux | 0:dd126a1080d3 | 298 | //Remember the input for the derivative calculation next time. |
| Knillinux | 0:dd126a1080d3 | 299 | prevProcessVariable_ = scaledPV; |
| Knillinux | 0:dd126a1080d3 | 300 | |
| Knillinux | 0:dd126a1080d3 | 301 | //Scale the output from percent span back out to a real world number. |
| Knillinux | 0:dd126a1080d3 | 302 | return ((controllerOutput_ * outSpan_) + outMin_); |
| Knillinux | 0:dd126a1080d3 | 303 | |
| Knillinux | 0:dd126a1080d3 | 304 | } |
| Knillinux | 0:dd126a1080d3 | 305 | |
| Knillinux | 0:dd126a1080d3 | 306 | float PID::getInMin() { |
| Knillinux | 0:dd126a1080d3 | 307 | return inMin_; |
| Knillinux | 0:dd126a1080d3 | 308 | } |
| Knillinux | 0:dd126a1080d3 | 309 | |
| Knillinux | 0:dd126a1080d3 | 310 | float PID::getInMax() { |
| Knillinux | 0:dd126a1080d3 | 311 | return inMax_; |
| Knillinux | 0:dd126a1080d3 | 312 | } |
| Knillinux | 0:dd126a1080d3 | 313 | |
| Knillinux | 0:dd126a1080d3 | 314 | float PID::getOutMin() { |
| Knillinux | 0:dd126a1080d3 | 315 | return outMin_; |
| Knillinux | 0:dd126a1080d3 | 316 | } |
| Knillinux | 0:dd126a1080d3 | 317 | |
| Knillinux | 0:dd126a1080d3 | 318 | float PID::getOutMax() { |
| Knillinux | 0:dd126a1080d3 | 319 | return outMax_; |
| Knillinux | 0:dd126a1080d3 | 320 | } |
| Knillinux | 0:dd126a1080d3 | 321 | |
| Knillinux | 0:dd126a1080d3 | 322 | float PID::getInterval() { |
| Knillinux | 0:dd126a1080d3 | 323 | return tSample_; |
| Knillinux | 0:dd126a1080d3 | 324 | } |
| Knillinux | 0:dd126a1080d3 | 325 | |
| Knillinux | 0:dd126a1080d3 | 326 | float PID::getPParam() { |
| Knillinux | 0:dd126a1080d3 | 327 | return pParam_; |
| Knillinux | 0:dd126a1080d3 | 328 | } |
| Knillinux | 0:dd126a1080d3 | 329 | |
| Knillinux | 0:dd126a1080d3 | 330 | float PID::getIParam() { |
| Knillinux | 0:dd126a1080d3 | 331 | return iParam_; |
| Knillinux | 0:dd126a1080d3 | 332 | } |
| Knillinux | 0:dd126a1080d3 | 333 | |
| Knillinux | 0:dd126a1080d3 | 334 | float PID::getDParam() { |
| Knillinux | 1:40bdbe1a93b7 | 335 | return dParam_; |
| Knillinux | 1:40bdbe1a93b7 | 336 | } |
| Knillinux | 0:dd126a1080d3 | 337 | |
| Knillinux | 1:40bdbe1a93b7 | 338 | float PID::getAccLimit() { |
| Knillinux | 1:40bdbe1a93b7 | 339 | return accLimit_; |
| Knillinux | 1:40bdbe1a93b7 | 340 | } |
| Knillinux | 0:dd126a1080d3 | 341 | |
| Knillinux | 1:40bdbe1a93b7 | 342 | float PID::getAccError() { |
| Knillinux | 1:40bdbe1a93b7 | 343 | return accError_; |
| Knillinux | 1:40bdbe1a93b7 | 344 | } |
| Knillinux | 1:40bdbe1a93b7 | 345 | |
| Knillinux | 1:40bdbe1a93b7 | 346 | |
| Knillinux | 1:40bdbe1a93b7 | 347 | float PID::getSetPoint() { |
| Knillinux | 1:40bdbe1a93b7 | 348 | return setPoint_; |
| Knillinux | 0:dd126a1080d3 | 349 | } |